Tire

ABSTRACT

A pneumatic tire is provided with a decoration portion at a tire side portion. The decoration portion includes decoration elements, which include ridges, and gullies, which are inclined with respect to the tire circumferential direction and divide the decoration elements into at least two regions. Thus, the gullies make the ridges non-continuous in the tire circumferential direction. The ridges include first ridges and second ridges that are smaller than the first ridges in one or both of height and width. At least some of the first ridges are inclined with respect to the tire circumferential direction and are adjacent to one another. Thus, the gullies are formed between the adjacent first ridges.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.13/509,718, filed May 14, 2012, which is a National Stage ofInternational Application No. PCT/JP2010/070612 filed Nov. 18, 2010,claiming priority based on Japanese Patent Application Nos. 2009-264285filed Nov. 19, 2009, JP 2009-284269 filed Dec. 15, 2009 and JP2010-009319 filed Jan. 19, 2010 the contents of all of which areincorporated herein by reference in their entirety.

TECHNICAL FIELD

The present invention relates to a tire provided with a decorationportion at a tire side portion.

BACKGROUND ART

Heretofore, the provision of side decoration bands in which pluralstraight or curved ridges are arranged in parallel at a side portion ofa tire has become widespread.

For example, in the Specification of U.S. Pat. No. 5,807,446, an exampleis disclosed in which a second ridge is formed inside a first ridge toform a side decoration band. Further, in Japanese Patent ApplicationLaid-Open (JP-A) No. 2008-273505, an example is disclosed in which aside decoration band is formed that includes a first decoration element,which is formed only by first ridges, and a second decoration element,in which second ridges are disposed inside the first ridges.

SUMMARY OF INVENTION Technical Problem

Although an effect of making unevenness at the side portion of a tireless obvious is provided in the Specification of U.S. Pat. No.5,807,446, there is little variation in silhouettes depending ondirections in which light arrives, and there is only a weak impact on aperson looking at the tire. In JP-A No. 2008-273505, an effect ofdifferentiating reflection states of light by combinations of decorationelements A and B and improving external appearance is provided. However,variations in strength of light and shade in accordance with variationsin the ridge heights are weak.

In consideration of the above circumstances, an object of the presentinvention is to provide a tire with which unevenness at a side portionis made less obvious and external appearance of the side portion isfurther improved.

Solution to Problem

A first aspect of the tire includes: a decoration portion at a tire sideportion, the decoration portion including: decoration elements thatinclude ridges; and depressions that are inclined with respect to a tirecircumferential direction, that divide the decoration elements into twoor more regions, and that make the ridges non-continuous in the tirecircumferential direction, wherein the ridges include; first ridges; andsecond ridges that are smaller than the first ridges in at least one ofheight or width, and wherein at least a portion of the first ridges areinclined with respect to the tire circumferential direction and areadjacent to one another, and the depressions are formed between theadjacent first ridges.

The tire will usually be a pneumatic tire but may be a solid tire thatis not filled with air. Some of the first ridges may each constitutedecoration elements at both sides of the first ridge. The decorationportion is not limited to the tire side portion and may be provided asfar as a shoulder portion or a bead portion or the like, provided suchare at the tire side face.

In the tire of the first aspect, because the decoration portion with theridges is provided at the tire side portion, unevenness of regions ofthe tire at which the decoration portion is provided may be made lessobvious. Because the ridges formed at the decoration portion include thefirst ridges and the second ridges, of which at least one of the heightand width is smaller than that of the first ridges, differences betweenthe presence and absence of light reflections and between brightnesses(the light and shade of shadows) may be effectively exhibited. Thus, apneumatic tire may be formed in which the appearance (aesthetics) of thetire side face is significantly improved.

In the first aspect, continuity in the tire circumferential direction ofthe ridges constituting the decoration elements is assuredly preventedby the gullies. Therefore, even when a force spreading in the tireradial direction acts on the tire side portion, cracks are unlikely tooccur at the decoration portion formed at the tire side portion.

Of the plural types of ridge, the first ridges are adjacent to oneanother and the gullies are formed therebetween. Therefore, there is noneed to make floor portions of the gullies lower than portions at whichthe ridges are not formed. Thus, the strength of regions of the tire atwhich the gullies are formed is significantly improved.

In a second aspect of the tire, the decoration elements include: firstdecoration elements, outer edge portions of which are formed by thefirst ridges, inner sides of the outer edge portions being smoothsurfaces; and second decoration elements, outer edge portions of whichare formed by the first ridges, the second ridges being arrayed at theinner side of the outer edge portions.

In the tire of the second aspect, because the inner side of the outeredge portion of each first decoration element is a smooth surface, theappearance of the first decoration element is unlikely to deteriorateeven if some amount of soiling such as dirt adheres. Further, becausethe inner side of the outer edge portion of the first decoration elementis the smooth surface, its reflectance of light is high and reflectionangles are consistent, and silhouettes against the second decorationelements are effectively made visible.

In a third aspect of the tire, the second decoration elements areconfigured as at least two types, respectively having differentdirections of the second ridges.

Thus, at the second decoration elements, reflection directions of thelight from the side wall faces of the second ridges are in at least twodirections, and silhouettes are made visible from at least twodirections.

In a fourth aspect of the tire, decoration element rows are formed bythe first decoration elements and the second declaration elements beingarranged alternately along the depressions, and the depressions arecontinuous along the decoration element rows between adjacent of thedecoration element rows.

Thus, the appearance of the gullies is better than if the gullies arenot continuous. Even though continuous gullies are formed, cracks areunlikely to occur at the gully floors.

In a fifth aspect of the tire, a direction in which the depressionsextend forms an angle with respect to the tire circumferential directionin a range of from 20° to 90°.

The above angle may be either of an angle to the rightward side relativeto the tire circumferential direction and an angle to the leftward side.

If this angle is less than 20°, tensile stresses at the gully floors andridge edges when a force spreading in the tire radial direction acts onthe tire side portion are likely to be larger.

With a view to suppressing tensile stresses at the gully floors andridge edges when a force spreading in the tire radial direction acts onthe tire side portion, it is more preferable if this angle is 70° orless.

In a sixth aspect of the tire, a floor width of the depressions is from0.2 mm to less than a maximum width of the decoration elements.

If the gully floor width is less than 0.2 mm, cracks are more likely tooccur at the gully floors. If the gully floor width is greater than thegreatest width of the decoration element, the appearance of thedecoration portion is likely to deteriorate.

In a seventh aspect of the tire, a height of the decoration elements isfrom 0.1 mm to less than 0.3 mm.

If the height is less than 0.1 mm, the visibility of the decorationelements is likely to decrease. If the height is 0.3 mm or greater, itmay be difficult to thoroughly prevent occurrences of cracks at thedecoration portion.

An eighth aspect of the tire is a pneumatic tire that includes, at atire side portion, a marked portion and a decoration portion, thedecoration portion being configured by a combination of a plurality oftypes of decoration element, and the plurality of types of decorationelements, including: first decoration elements that are formed only byfirst ridges forming decoration element outlines; and second decorationelements including the first ridges forming decoration element outlines,and second ridges that are arranged in regions demarcated by the firstridges and that are lower in height than the first ridges.

In the tire of the eighth aspect, where the decoration elements areadjacent to one another, the decoration elements may share portions ofthe first ridges. The decoration portion is not limited to the tire sideportion and may be provided as far as a shoulder portion or a beadportion or the like, provided such are at the tire side face. The tirewill usually be a pneumatic tire but may be a solid tire that is notfilled with air.

In the tire of the eighth aspect, because the decoration portionincluding the first decoration elements and the second decorationelements is provided at the tire side portion, unevenness of regions ofthe tire at which the decoration portion is provided may be made lessobvious. Because the second ridges whose heights are lower than thefirst ridges are disposed at the second decoration elements, differencesbetween the presence and absence of light reflections and betweenbrightnesses (the light and shade of shadows) may be effectivelyexhibited. Thus, a pneumatic tire may be formed in which the appearance(aesthetics) of the tire side face is significantly improved.

In a ninth aspect of the tire, in the first decoration elements,interiors of regions surrounded by the first ridges are smooth surfaces.

Thus, at a region inside the first ridges constituting each firstdecoration element, the reflectance of light is high and reflectionangles are consistent, and silhouettes against the second decorationelements are effectively made visible.

In a tenth aspect of the tire, inclination angles of side walls differbetween the first ridges and the second ridges.

Thus, because the reflection directions differ between the inclinedfaces of the first ridges and the inclined faces of the second ridges,the first ridges and second ridges may be clearly distinguished bysight.

In an eleventh aspect of the tire, the first decoration elements andsecond decoration elements are arranged cyclically in the decorationportion.

Thus, an effect of uniformity and regularity being apparent is furtherprovided.

In a twelfth aspect of the tire, the first ridges are configured by aplurality of linear ridges of arbitrary direction.

Thus, even with a simple structure in which positions of arrangement ofthe first decoration elements and the second decoration elements are notperiodically aligned, because the first ridges have greater heights thanthe second ridges, a pneumatic tire whose appearance is significantlyimproved may be formed.

In a thirteenth aspect of the tire, the first decoration elements andthe second decoration elements are disposed in at least a portion of aperiphery of the marked portion.

Thus, the visibility of the marked portion is improved, which is to say,the visibility of marks is improved.

In a fourteenth aspect of the tire, the ridges are arrayed in aperipheral region of the marked portion that does not include any marks,and the marks are presented as smooth surfaces.

Thus, the visibility of the marks is further improved and the impact ona person viewing the marks is substantial. It is preferable, with a viewto making marks for which the importance of visibility is high moreprominent, that two or more decoration portions be formed at the tireside portion and that the decoration portions be disposed at both sidesof a marked portion in the tire circumferential direction.

A fifteenth aspect of the tire includes a decoration portion at a tireside portion, the decoration portion including a plurality of decorationelements, and the decoration elements including: first decorationelements that are formed only by first ridges forming decoration elementoutlines; second decoration elements that are configured by the firstridges and second ridges that are arranged inside the first ridges; andthird decoration elements that differ from the second decorationelements in terms of arrangement of the second ridges.

In the tire of the fifteenth aspect, where the first to third decorationelements are adjacent to one another, the first to third decorationelements may form plural combinations, even if the decoration elementsshare portions of the first ridges with one another.

In the tire of the fifteenth aspect, because the decoration portionformed of plural combinations of the first to third decoration elementsis provided at the tire side portion, unevenness of regions of the tireat which the decoration portion is provided may be made less obvious.Because the arrangements of the second ridges differ between the seconddecoration elements and the third decoration elements, differencesbetween shadows due to differences in the ways light (sunlight,environmental light, etc.) is reflected may be effectively exhibited.Thus, a tire may be formed in which the appearance (aesthetics) of thetire side portion is significantly improved.

In a sixteenth aspect of the tire, in the first decoration elements,regions inside the first ridges are smooth surfaces.

Thus, at regions inside the first ridges constituting the firstdecoration elements, the reflectance of light is high and reflectionangles are consistent, and silhouettes against the second decorationelements and the third decoration elements are effectively made visible.

In a seventeenth aspect of the tire, directions of extension of thesecond ridges differ between the second decoration elements and thethird decoration elements.

Thus, differences in brightness (light and shade of shadows) due todifferences in the reflection directions of light may be effectivelyexhibited between the second decoration elements and the thirddecoration elements.

In an eighteenth aspect of the tire, pitches of the second ridges differbetween the second decoration elements and the third decorationelements.

Thus, differences in shadows due to the difference in pitch between thesecond decoration elements and the third decoration elements may beeffectively exhibited. This is particularly effective for makingbrightness differences between the second decoration elements and thethird decoration elements sufficiently visible when incident amounts oflight on the tire side portion are small.

In a nineteenth aspect of the tire, the first decoration elements, thesecond decoration elements and the third decoration elements arearranged cyclically in the decoration portion.

Thus, uniformity and regularity of the decoration portion are apparent,and unevenness of regions in which the declaration portion is formed maybe made less obvious.

A twentieth aspect of the tire further includes a marked portion at thetire side portion that displays marks, wherein the first decorationelements and the second decoration elements are disposed in at least aportion of a periphery of the marked portion.

Thus, the visibility of the marked portion is improved, which is to say,the visibility of marks is improved.

In a twenty-first aspect of the tire, the ridges are arrayed in aperiphery region of the marked portion that does not include the marks,and the marks are presented as smooth surfaces.

Thus, the visibility of the marks is further improved and the impact ona person viewing the marks is substantial. It is preferable, with a viewto making marks for which the importance of visibility is high moreprominent, that two or more decoration portions be formed and that thedecoration portions be disposed at both sides of the marked portion inthe tire circumferential direction.

Advantageous Effects of Invention

According to the present invention, a tire with which unevenness at aside portion is made less obvious and appearance of the side portion isfurther improved may be formed.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side view of the vehicle outer side of a pneumatic tire inaccordance with a first exemplary embodiment.

FIG. 2 is a side view of the vehicle inner side of the pneumatic tire inaccordance with the first exemplary embodiment.

FIG. 3 is a partial enlarged view of a decoration portion formed at aside portion of the pneumatic tire in accordance with the firstexemplary embodiment.

FIG. 4A is a partial enlarged view of a decoration portion formed at theside portion of the pneumatic tire in accordance with the firstexemplary embodiment.

FIG. 4B is a partial enlarged view of the decoration portion formed atthe side portion of the pneumatic tire in accordance with the firstexemplary embodiment, being a view showing an outward triangular shape.

FIG. 4C is a partial enlarged view of the decoration portion formed atthe side portion of the pneumatic tire in accordance with the firstexemplary embodiment, being a view showing an inward triangular shape.

FIG. 5 is a partial enlarged view of a decoration portion formed at theside portion of the pneumatic tire in accordance with the firstexemplary embodiment.

FIG. 6 is a sectional diagram showing first ridges constituting thedecoration portion of the side portion of the pneumatic tire inaccordance with the first exemplary embodiment.

FIG. 7A is a descriptive diagram of a process step, illustrating theformation of recess portions that correspond with the first ridges andsecond ridges in a mold that fabricates the pneumatic tire in accordancewith the first exemplary embodiment.

FIG. 7B is a descriptive diagram of a process step, illustrating theformation of the recess portions that correspond with the first ridgesand the second ridges in the mold that fabricates the pneumatic tire inaccordance with the first exemplary embodiment.

FIG. 8 is a partial enlarged view showing a variant example of thedecoration portion formed at the side portion of the pneumatic tire inaccordance with the first exemplary embodiment.

FIG. 9 is a side view of a pneumatic tire in accordance with a secondexemplary embodiment.

FIG. 10 is a partial enlarged side view of a side decoration band of thepneumatic tire in accordance with the second exemplary embodiment.

FIG. 11 is a descriptive diagram of a concept of arrangement of firstdecoration elements and second decoration elements in the secondexemplary embodiment.

FIG. 12 is a sectional diagram viewed from line 4-4 of FIG. 10.

FIG. 13 is a partial enlarged side view of a side decoration band of apneumatic tire in accordance with a third exemplary embodiment.

FIG. 14A is a partial enlarged side view of a side decoration band of apneumatic tire in accordance with a fourth exemplary embodiment.

FIG. 14B is an enlarged view of a first principal portion in FIG. 14A.

FIG. 14C is an enlarged view of a second principal portion in FIG. 14A.

FIG. 15 is a descriptive diagram of a concept of arrangement of firstdecoration elements and second decoration elements in the fourthexemplary embodiment.

FIG. 16 is a partial enlarged side view of a side decoration band of apneumatic tire in accordance with a fifth exemplary embodiment.

FIG. 17 is a descriptive diagram of a concept of arrangement of thefirst decoration elements and the second decoration elements in thefifth exemplary embodiment.

FIG. 18A is a partial enlarged side view of a side decoration band of apneumatic radial tire in accordance with a sixth exemplary embodiment.

FIG. 18B is an enlarged view of principal portions in FIG. 18A.

FIG. 19 is a partial enlarged side view of a variant example of the sidedecoration band of the pneumatic tire in accordance with the sixthexemplary embodiment.

FIG. 20 is a partial enlarged side view of a side decoration band of apneumatic tire in accordance with a seventh exemplary embodiment.

FIG. 21 is a side view of a pneumatic tire in accordance with an eighthexemplary embodiment.

FIG. 22A is a partial enlarged side view of a tire side portion of apneumatic tire in accordance with the eighth exemplary embodiment.

FIG. 22B is an enlarged view of principal portions in FIG. 22A.

FIG. 23 is a descriptive diagram of a concept of arrangement of firstdecoration elements and second decoration elements in the eighthexemplary embodiment.

FIG. 24 is a sectional diagram viewed from line 4-4 of FIG. 22B.

FIG. 25 is a sectional diagram viewed from line 5-5 of FIG. 22B.

FIG. 26 is a partial enlarged side view of a side decoration band of apneumatic tire in accordance with a ninth exemplary embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

Herebelow, embodiments are presented and explained as exemplaryembodiments of the present invention. FIG. 1 is a side view of thevehicle outer side of a pneumatic tire 10 in accordance with a presentexemplary embodiment. FIG. 2 is a side view of the vehicle inner side ofthe pneumatic tire 10 in accordance with the present exemplaryembodiment.

—Vehicle Outer Side of Pneumatic Tire—

As illustrated in FIG. 1, two side decoration bands 16 in circular arcshapes are formed at a side portion 14 at the vehicle outer side of thepneumatic tire 10. The two side decoration bands 16 are formed so as tobe disposed at symmetrical positions sandwiching a tire central axis C(see FIG. 1). Numerous ridges 18 that are inclined with respect to atire circumferential direction U are arrayed in each side decorationband 16.

t the side portion 14, marked portions 20 are formed in circular arcshapes between one side decoration band 16J and the other sidedecoration band 16K. Thus, two of the marked portions 20 are formed soas to be disposed at symmetrical positions sandwiching the tire centralaxis C. Marks 22 are displayed as, for example, the characters“ABCDEFGH”, which are presented as smooth surfaces.

Decoration portions 24 are formed between the side decoration bands 16and the marked portions 20. Thus, the decoration portions 24 are formedat four locations.

—The Decoration Portion 24—

Each decoration portion 24 is constituted by two decorationhalf-portions 24A and 24B that are adjacent to one another in the tirecircumferential direction U. The decoration half-portions 24A and 24Bare both formed in parallelogram shapes, the decoration half-portion 24Ais disposed a little to the tire outer periphery side and the decorationhalf-portion 24B is disposed a little to the tire inner periphery side.

As illustrated in FIG. 3, first ridges 26, second ridges 28 and gullies32 are formed at each of the decoration half-portions 24A and 24B. Thefirst ridges 26 extend in directions angled at an inclination angle θ ofaround 45° with respect to the tire circumferential direction U. Thesecond ridges 28 are smaller than the first ridges 26 in one or both ofheight and width. The gullies 32 extend in directions that are inclinedwith respect to the tire circumferential direction U. Each gully 32 isformed by and between first ridges 26 that are adjacent to one another.The gullies 32 divide decoration elements that form each decorationhalf-portion 24A into plural regions, and the same applies at thedecoration half-portion 24B.

Giving a detailed description, triplet first ridges 26P and doubletfirst ridges 26Q are formed at the decoration half-portions 24A and 24B.The triplet first ridges 26P have three wave shapes extending inparallel from the lower right to the upper left of the drawing of FIG. 3(that is, in a direction that is inclined from the tire radial directioninner side toward the outer side relative to the tire circumferentialdirection U in a tire side view). The doublet first ridges 26Q have twowave shapes extending in parallel from the lower left of the drawingtoward the upper right. The respective ridges constituting the tripletfirst ridges 26P and doublet first ridges 26Q are all constituted by thefirst ridges 26. Gullies 32P with pairs of wave shapes extending atangles relative to the tire circumferential direction U are formed bythe triplet first ridges 26P, and gullies 32Q with single wave shapesextending at angles relative to the tire circumferential direction U areformed by the doublet first ridges 26Q. The gullies 32P are continuousfrom one end to the other end of each of the decoration half-portions24A and 24B.

The triplet first ridges 26P are plurally arrayed at equal intervals,and the doublet first ridges 26Q are plurally arrayed at equalintervals. Decoration element rows 34P are formed between adjacenttriplet first ridges 26P along the triplet first ridges 26P (that is,along the gullies 32P). In each decoration element row 34P, firstdecoration elements 36 and second decoration elements 38 are alternatelyarrayed.

Each first decoration element 36 is a decoration element whose outeredge portions are formed by the first ridges 26 and at the inside of theouter edge portions of which a smooth surface 37 is formed. Each seconddecoration element 38 is a decoration element whose outer edge portionsare formed by the first ridges 26 and at the inside of the outer edgeportions of which a plural number of the second ridges 28 are arrayedparallel to one another. The second ridges 28 are ridges that extend instraight lines from the lower left toward the upper right of thedrawing.

Decoration element rows 34Q are formed between adjacent doublet firstridges 26Q along the doublet first ridges 26Q (that is, along thegullies 32Q). In each decoration element row 34Q too, positions of theabove-mentioned smooth surfaces 37 and second ridges 28 are set in astaggered pattern such that the first decoration elements 36 and seconddecoration elements 38 are alternately arrayed.

Example of Favorable Dimensions

Below, a specific favorable example of the first ridges 26 and secondridges 28 at the pneumatic tire 10 relating to the present exemplaryembodiment, and spacings thereof and suchlike, is illustrated. FIG. 6 isa sectional diagram viewed from line 6-6 of FIG. 3.

As illustrated in FIG. 6, each first ridge 26 has a trapezoid shape incross-section. A width B1 of a flat surface 26F forming a top portion ofthe first ridge 26 is a maximum of 0.2 mm. Inclined faces (side faces)26S of the first ridge 26 form angles α of 45° with respect to a normaldirection N of the side decoration band 16. A height h1 of the firstridge 26 is 0.2 mm. A spacing (pitch) P between adjacent first ridges is1.0 mm, and a floor width W1 between the adjacent first ridges 26 is 0.4mm. With this specification, given a machining crossover of 0.5 mm for afirst recess portion 44 that forms the first ridges 26, which isdescribed later, even at a minimum the floor width WS is 0.3 mm (amaximum height hM of the first ridge 26 in this case is 0.25 mm). If thefloor width W1 is more than 0.2 mm, a structure in which cracks areunlikely to occur at the floor portions of the gullies 32 may be formed.Thus, the occurrence of cracks may be thoroughly prevented with thisdimensional example.

Each second ridge 28 is also a trapezoid in cross-section. A structuremay be formed in which the second ridges 28 have a lower height than thefirst ridges 26 or the width of the flat surface forming the top portionof each second ridge 28 is narrower than that of each first ridge 26.Further, a structure may be formed in which both the second ridges 28have a lower height than the first ridges 26 and the widths of the flatsurfaces forming the top portions of the second ridges 28 are narrowerthan those of the first ridges 26.

Favorable dimensional ranges of the first decoration element 36 and thesecond decoration element 38 are lengths in the tire circumferentialdirection being in a range from 2 mm to 10 mm, and lengths in the tireradial direction being in a range from 2 mm to 10 mm. It is preferableif the pitch of the second ridges 28 is at least 0.5 mm with a view topreventing the occurrence of cracks between adjacent second ridges 28,and it is preferable if the pitch is at most 1.5 mm with a view toappearance.

The first ridges 26 and second ridges 28 may be formed duringvulcanization molding by recess portions being formed in advance atinner wall faces of a mold for vulcanization molding of a green tire.

In the present exemplary embodiment, as illustrated in FIG. 7A and FIG.7B, second recess portions 42 for forming the second ridges 28 areformed at mold inner wall portions 48 for forming the second decorationelements 38 (see FIG. 7A) and first recess portions 44 for forming thefirst ridges 26 are formed at the mold inner wall portions 48 (see FIG.7B).

If there is a region in which the second recess portions 42 arenon-continuous, and the first recess portions 44 are formed in thenon-continuous region, a drill for forming the first ridges 26 is movedwhile cutting first recess portion preparatory portions 44Y. Forexample, one second recess portion 42M is formed by the drill, up to anend portion thereof, and then the drill is moved while cutting the firstrecess portion preparatory portions 44Y up to a position of an endportion of an adjacent second recess portion preparatory portion. Thenthe drill forms the adjacent second recess portion 42N.

After the second recess portions 42 have been formed with a single lineas described above, the first recess portions 44 are formed by thedrill. Hence, as illustrated in FIG. 7B, the first recess portions 44are formed at the first recess portion preparatory portions 44Y, and notraces are left of the first recess portion preparatory portions 44Ythat were cut by the drill cutting the second recess portions 42. Thus,the second recess portions 42 may be formed in a short time with asingle line.

—Vehicle Inner Side of Pneumatic Tire—

As illustrated in FIG. 2, similarly to the side portion 14 at thevehicle outer side, two circular arc-shaped side decoration bands 16 andtwo circular arc-shaped marked portions 20 are formed at a side portion54 at the vehicle inner side of the pneumatic tire 10.

Decoration portions 64 are formed between one side decoration band 16and the marked portions 20. Thus, the decoration portion 64 is formed ateach of two locations at the two tire circumferential direction endsides of the one side decoration band 16.

Decoration portions 66 are formed between the other side decoration band16 and the marked portions 20. Thus, the decoration portion 66 is formedat each of two locations at the two tire circumferential direction endsides of the other side decoration band 16.

—The Decoration Portion 64—

Each decoration portion 64 is constituted by two decorationhalf-portions 64A and 64B that are adjacent to one another in the tirecircumferential direction U. The decoration half-portions 64A and 64Bboth have outer shapes formed as parallelograms, the decorationhalf-portion 64A is disposed a little to the tire outer periphery sideand the decoration half-portion 64B is disposed a little to the tireinner periphery side.

As illustrated in FIG. 4A, first ridges 76, second ridges 78 and gullies82 are formed at both of the decoration half-portions 64A and 64B. Thefirst ridges 76 extend in straight lines in directions that are inclinedwith respect to the tire circumferential direction U. The second ridges78 are smaller than the first ridges 76 in one or both of height andwidth. The gullies 82 extend in directions that are inclined withrespect to the tire circumferential direction U. Each gully 82 is formedby and between the first ridges 76. Each gully 82 is formed by andbetween the first ridges 76. The gullies 82 divide decoration elementsthat form the decoration half-portion 64A into plural regions, and thesame applies at the decoration half-portion 64B.

Giving a detailed description, each first ridge 76 extends in adirection angled at an inclination angle δ of about 60° relative to thetire circumferential direction U. In the decoration half-portions 64Aand 64B, doublet first ridges 76Q are formed, in each of which tworidges extend in parallel from the lower left to the upper right of thedrawing of FIG. 4A. Each doublet first ridge 76Q is constituted by twoof the first ridges 76. Between the parallel first ridges 76constituting the doublet first ridges 76Q, the gullies 82 are formedextending at an angle with respect to the tire circumferential directionU. Each gully 82 is continuous from one end to the other end of thedecoration half-portion 64A or 64B.

The doublet first ridges 76Q are plurally arrayed at equal intervals.Between adjacent doublet first ridges 76Q, decoration element rows 84are formed along the gullies 82. In each decoration element row 84,first decoration elements 86 and second decoration elements 88 arealternately arrayed.

In the present exemplary embodiment, equilateral triangular shapes 92that are protrusions to the radial direction outer side (hereinafterreferred to as outward triangular shapes 92) and equilateral triangularshapes 94 that are protrusions to the radial direction inner side(hereinafter referred to as inward triangular shapes 94) are formed bythe first decoration elements 86 and second decoration elements 88.

Each first decoration element 86 is formed by first ridges 76 that formouter edge portions of an isosceles triangle with an internal angle of120°, and a smooth surface 77 with an isosceles triangle shape that isformed inside the first ridges 76. Each second decoration element 88 isformed by first ridges 76 that form outer edge portions of an isoscelestriangle with an internal angle of 120°, and second ridges 78 that arearrayed inside the first ridges 76. In the present exemplary embodiment,the second ridges 78 extend in the tire radial direction R.

Each outward triangular shape 92 (see FIG. 4B) is constituted by two ofthe first decoration elements 86 that are adjacent to one another, andone of the second decoration elements 88. The two first decorationelements 86 share a first ridge 76P at the region at which they adjoinone another, and the first ridge 76P structures both of these firstdecoration elements 86.

Each inward triangular shape 94 (see FIG. 4C) is constituted by one ofthe first decoration elements 86, and two of the second decorationelements 88. The two second decoration elements 88 share a first ridge76P at the region at which they adjoin one another, and the first ridge76P structures both of these second decoration elements 88.

The outward triangular shapes 92 and inward triangular shapes 94 arearrayed alternately along the gullies 82.

—The Decoration Portion 66—

Each decoration portion 66 is constituted by two decorationhalf-portions 66A and 66B that are adjacent to one another in the tirecircumferential direction U. The decoration half-portions 66A and 66Bboth have outer shapes formed as parallelograms, the decorationhalf-portion 66A is disposed a little to the tire outer periphery sideand the decoration half-portion 66B is disposed a little to the tireinner periphery side.

As illustrated in FIG. 5, lattice ridges 98 are formed in the decorationhalf-portions 66A and 66B by ridges that extend from the lower right tothe upper left of the drawing and ridges that extend from the lower leftto the upper right of the drawing.

As described hereabove, according to the present exemplary embodiment,the decoration portions 24 and 64 containing ridges are provided at thetire side portions. Thus, unevenness of the regions of the tire in whichthese decoration portions are provided may be made less obvious. Theridges formed in the decoration portion 24 include the first ridges 26and the second ridges 28 of which at least one of the height and widthis greater than that of the first ridges 26. The ridges formed in thedecoration portion 64 include the first ridges 76 and the second ridges78 of which at least one of the height and width is greater than that ofthe first ridges 76. Therefore, differences between the presence andabsence of light reflections and between brightnesses (the light andshade of shadows) may be effectively exhibited. Thus, a pneumatic tiremay be formed in which the appearance (aesthetics) of the tire sidefaces is significantly improved.

Furthermore, according to the present exemplary embodiment, thedecoration portions 24 of the side portion 14 include the plural gullies32 (32P and 32Q) that are inclined with respect to the tirecircumferential direction U, and the first decoration elements 36 andsecond decoration elements 38 that are formed at both sides of eachgully 32. Therefore, the first ridges 26 and second ridges 28constituting the first decoration elements 36 and second decorationelements 38 are assuredly prevented from being continuous in the tirecircumferential direction U by the gullies 32. Therefore, even when aforce spreading in the tire radial direction (the tire diametricdirection) R acts on the side portion 14, cracks are unlikely to occurat the decoration portions 24. This provides a particularly strikingeffect if there is a step at a rear face side of the side portion 14,due to folded ends of the carcass ply or the like, and the decorationportion 24 is disposed at a position straddling this step.

The first ridges 26 are inclined with respect to the tirecircumferential direction U and are adjacent to one another, and thegullies 32 are formed between the adjacent first ridges 26. Therefore,there is no need for the floors of the gullies 32 to be set lower thansmooth portions such as the smooth surfaces 37 and the like. Inconsequence, the strength of regions of the tire at which the gullies 32are formed is sufficiently high.

Because the inner side of the outer edge portion of each firstdecoration element 36 is the smooth surface 37, the appearance of thefirst decoration element 36 is unlikely to deteriorate even if someamount of soiling such as dirt adheres. Further, the reflectance oflight is raised by the smooth surface 37 and reflection angles areconsistent, and silhouettes against the second decoration elements 38are effectively made visible. Moreover, compared with forming ridges atthe inside of each first decoration element 36, forming the smoothsurfaces 37 may reduce the number of steps in machining of a mold andthe like.

The decoration element rows 34P and 34Q are formed in each decorationportion 24. In each decoration element row 34P, the first decorationelements 36 and second decoration elements 38 are disposed alternatelyalong the gullies 32P, and in each decoration element row 34Q, the firstdecoration elements 36 and second decoration elements 38 are disposedalternately along the gullies 32Q. The gullies 32 (32P and 32Q) extendso as to be continuous from end to end of the decoration element rows.Thus, the appearance of the gullies 32 is better than if the gullieswere not continuous, and even though the continuous gullies 32 areformed, cracks are unlikely to occur in the gully floors.

Because each gully 32 forms an angle θ of around 45° with the tirecircumferential direction U, even if a force spreading in the tireradial direction R or a force spreading in the tire circumferentialdirection U or the like acts on the side portion 14, tensile stresses atthe floor portions of the gullies 32 and ridge floor edges (particularlyridge floor edges of the first ridges 26) or the like are thoroughlyprevented from increasing. The angle 8 is not limited to 45° and may bean angle in a range from 20° to 90°. Thus, tensile stresses at the floorportions and ridge edges of the gullies 32 or the like when a forcespreading in the tire radial direction R acts on the side portion 14 maybe effectively lowered. In regard to suppressing the tensile stressesoccurring at the floor portions and ridge bottom edges of the gullies 32or the like when a force spreading in the tire circumferential directionU acts on the side portion 14, it is preferable if the angle 8 is notmore than 70°.

At the decoration portions 64 at the vehicle inner side portion 54 too,the plural gullies 82 are formed at angles with respect to the tirecircumferential direction U, the first decoration elements 86 and seconddecoration elements 88 are formed between adjacent gullies 82, andsimilar effects are realized as at the decoration portions 24 at thevehicle inner side portion 14.

It is preferable if floor widths of the gullies 32 are at least 0.2 mmbut not more than a maximum width of the first decoration elements 36and second decoration elements 38. Thus, a structure may be formed inwhich cracks are unlikely to occur at the floors of the gullies 32,without the appearance of the decoration portion 24 being adverselyaffected. The same applies to the gullies 82.

It is preferable if the heights of the first decoration elements 36 andsecond decoration elements 38, that is, the heights of the first ridges26 and 76 and the second ridges 28 and 78, are at least 0.1 mm but lessthan 0.3 mm. Thus, occurrences of cracks in the decoration portions 24may be thoroughly prevented without the appearance of the firstdecoration elements 36 and second decoration elements 38 being adverselyaffected. The same applies to the first decoration elements 86 andsecond decoration elements 88.

Further modes may be formed with ridges or the like instead of thesmooth surfaces 37 and 77. For example, as illustrated in FIG. 8, secondridges 79 may be arrayed instead of the smooth surfaces 37 (see FIG. 3).In this case, the directions of the second ridges 79 are arranged so asto differ by 90° from the directions of the second ridges 28. Thus,light reflection directions from the second ridges 28 and the secondridges 79 are different by 90°. Consequently, the light and shade ofshadows change in a regular manner depending on differences in viewingdirections, and the appearance (aesthetics) of the tire side face isfurther improved.

In the present embodiment, an example is described in which thedecoration portions 24 are formed at four locations of the side portion14 at the vehicle outer side, and at the side portion 54 at the vehicleinner side, the decoration portions 64 are formed at both tirecircumferential direction end sides of one of the side decoration bands16 and the decoration portions 66 are formed at both tirecircumferential direction end sides of the other side decoration band16. However, the present invention is not limited thus. The decorationportions 24 and the decoration portions 64 may be disposed at the sideportion 14 at the vehicle outer side, and the number of decorationportions may be a number greater or a number smaller than four.

Second Exemplary Embodiment

Next, a second exemplary embodiment is described. FIG. 9 is a side viewof a pneumatic tire 100 in accordance with the present exemplaryembodiment. As shown in FIG. 9 and FIG. 10, two side decoration bands116 in circular arc shapes (see FIG. 9 and FIG. 10) are formed at a sideportion 114 of the pneumatic tire 100. Each side decoration band 116 isformed by a combination of plural first decoration elements 120 andsecond decoration elements 122. The first decoration elements 120 areformed only by first ridges 126 that form an outline of a smooth surfaceregion 124 with a specified shape. The second decoration elements 122are constituted by the first ridges 126 that form outlines, and secondridges 128 that are arrayed inside the first ridges 126. The firstdecoration elements 120 and second decoration elements 122 that areadjacent to one another share the first ridges 126.

Two of the two side decoration bands 116 are formed so as to be disposedat symmetrical positions sandwiching the tire central axis C (see FIG.9).

At the side portion 114, marked portions 130 are formed in circular arcshapes so as to be adjacent at respective both end portions thereof withone side decoration band 116 and the other side decoration band 116.Thus, two of the marked portions 130 are formed so as to be disposed atsymmetrical positions sandwiching the tire central axis C. Marks 132 aredisplayed as, for example, the characters “ABCDEF”, which are presentedas smooth surfaces. Numerous ridges 134 are arrayed in surroundingregions 136 of the marked portions 130 excluding the marks 132.

As shown in FIG. 10, in each side decoration band 116, the firstdecoration elements 120 and the second decoration elements 122 arearranged periodically. Giving a detailed description, in the sidedecoration band 116, the first decoration elements 120 and the seconddecoration elements 122 are arranged alternately in the tirecircumferential direction U and in the tire radial direction (in acheckered pattern). The concept of arranging the first decorationelements 120 and the second decoration elements 122 alternately thus isdescribed in FIG. 11. As shown in FIG. 11, in the present exemplaryembodiment, positions of arrangement of the first decoration elements120 and the second decoration elements 122 are offset.

Of each first decoration element 120, the smooth surface region 124surrounded by the first ridges 126 is constituted by a long, narrowportion 124L, with a substantially rectangular shape that is long in thetire circumferential direction U, and an extending portion 124T, with asubstantially square shape that extends toward the tire radial directioninner side from a tire circumferential direction central portion of thelong, narrow portion 124L. Because the outline of the smooth surfaceregion 124 is formed by the first ridges 126, the first decorationelement 120 has a shape that appears as a “T” oriented to the tireradial direction inner side.

Each second decoration element 122 has a shape that appears as a “T”oriented to the tire radial direction outer side. The second ridges 128constituting the second decoration element 122 are ridges extending inthe tire radial direction R.

As described above, in the present exemplary embodiment the sidedecoration band 116, in which the first decoration elements 120 and thesecond decoration elements 122 are disposed alternately in the tirecircumferential direction U and the tire radial direction R, is formedat the side portion 114. Each first decoration element 120 is formedonly by the first ridges 126 that form the outline of the smooth surfaceregion 124. Each second decoration element 122 is constituted by thesecond ridges 128 whose heights are lower than the first ridges 126being arrayed. The first ridges 126 serve the function of framing thedecoration pattern, and the second ridges 128 serve the function ofimproving visibility. In the side decoration band 116, because the firstdecoration elements 120 and the second decoration elements 122 arecontinuously formed alternately, unevenness of regions in which the sidedecoration band 116 is formed may be made less visible. Moreover, thepresence and absence of light reflections and brightnesses (the lightand shade of shadows) may be effectively exhibited. In addition, becausea reflection direction from the smooth surface regions 124 is a singledirection, glossy shades are distinct and a sense of high quality may beimparted, and the appearance (aesthetics) is improved. This isparticularly striking if a wax is applied to the side decoration band116. Because the first ridges 126 have greater heights than the secondridges 128, the appearance is significantly improved compared to a casein which the heights are the same. The dimensions of the first ridges126 and the second ridges 128 may be made different by making themachining depths different when the ridges are being formed by tooling,etching or the like.

Because the first decoration elements 120 and the second decorationelements 122 have the same shapes apart from the orientations beingopposite, the side decoration band 116 appears with uniformity andregularity, and a further effect of making unevenness of the sidedecoration band 116 less visible is obtained.

In each side decoration band 116, the first decoration elements 120 andthe second decoration elements 122 are arranged periodically (arrangedin a checkered pattern). Therefore, the appearance (aesthetics) isexcellent. Contrasts in brightness occur clearly with the presence andabsence of the second ridges 128 whose boundaries are the outlinesformed by the first ridges 126, and visibility of the side decorationband 116 formed by the first decoration elements 120 and the seconddecoration elements 122 is further improved.

In the present exemplary embodiment, the pneumatic tire 100 is providedwith the marked portions 130 at the tire side face. The marked portions130 display the marks 132 and are adjacent with the first decorationelements 120 and the second decoration elements 122 at respective bothends thereof. Thus, the visibility of the marked portions 130 isimproved, which is to say, visibility of the marks 132 is improved.

The marks 132 are displayed as smooth surfaces, and the ridges 134 (forexample, straight or curved ridges) are arrayed in the surroundingregions 136 of the marked portions 130 excluding the marks 132. Thus,the visibility of the marks 132 is further improved and the impact on aperson viewing the marks 132 is substantial.

In the present exemplary embodiment, the direction of extension of thesecond ridges 128 is the tire radial direction R, but the presentinvention is not limited thus and the direction may be a directionintersecting the tire radial direction R.

Below, a specific favorable example of the first ridges 126 and secondridges 128, and spacings thereof and suchlike, is illustrated. FIG. 12is a sectional diagram viewed from line 4-4 of FIG. 10. As shown in FIG.12, each first ridge 126 has a trapezoid shape in cross-section. A widthB10 of a flat surface 126F forming a top portion of the first ridge 126is a maximum of 0.2 mm. Inclined faces (side faces) 126S of the firstridge 126 form angles α1 of 45° with respect to a normal direction N ofthe side decoration band 116. A height h10 of the first ridge 126 is 0.2mm. A height h30 of a dividing ridge 138 that extends in the tire radialdirection R and divides the side decoration band 116 from the markedportions 130 is 0.4 mm.

Each second ridge 128 is also a trapezoid in cross-section. A width B20of a flat surface 128F forming a top portion of the second ridge 128 isa maximum of 0.2 mm. Inclined faces (side faces) 128S of the secondridge 128 form angles α2 of 35° with respect to a normal direction N ofthe side decoration band 116. A height h20 of the second ridge 128 is0.15 mm. A spacing d20 between adjacent second ridges 128 is 0.6 mm.

Thus, because the inclination angles of the inclined faces 126S of thefirst ridges 126 and the inclined faces 128S of the second ridges 128are different (α1 and α2 are different), the function of framing thedecoration patterns by the first ridges 126 and the function ofimproving visibility of the patterns by the second ridges 128 may bemore clearly implemented. Because of the relationships h10>h20 andα1>α2, this is realized even further.

As long as the height h10 of the first ridges 126 is greater than theheight h20 of the second ridges 128, sufficient effects of visibility,endurance and the like will be realized, provided these dimensions arewithin a range of ±50% of the values illustrated here, preferably withina range of ±30%.

Third Exemplary Embodiment

Next, a third exemplary embodiment is described. In the presentexemplary embodiment, as shown in FIG. 13, first decoration elements 150and second decoration elements 152 are respectively spaced apart andarranged in the side decoration band 116 of the side portion 114 of thepneumatic tire 100 shown in FIG. 9. Compared with the first decorationelement 120 described in the second exemplary embodiment, each firstdecoration element 150 is inverted in the up—down direction of thedrawing (the tire radial direction R), and has a first ridge 156, whichhas the same cross-sectional dimensions as the first ridges 126, formedsurrounding a smooth surface region 154. Compared with the seconddecoration element 122 described in the second exemplary embodiment,each second decoration element 152 has a first ridge 158, which has thesame cross-sectional dimensions as the first ridges 126, formedtherearound. The second ridges 128 are arrayed inside the first ridge158.

In the present exemplary embodiment, the first ridges 156 and 158 servethe function of framing the decoration pattern, and the second ridges128 serve the function of improving visibility. Because of the secondridge patterns, differences between the presence and absence of lightreflections and between brightnesses (the light and shade of shadows)may be effectively exhibited. In addition, because a reflectiondirection from the smooth surface regions 154 is a single direction, theappearance (aesthetics) may be improved.

Fourth Exemplary Embodiment

Next, a fourth exemplary embodiment is described. In the presentexemplary embodiment, as shown in FIG. 14A, a side decoration band 166in a circular arc shape that is formed of a combination of plural firstdecoration elements 170 and second decoration elements 172 (seconddecoration elements 172A and 172B hereinafter) is formed at the sideportion 114 of the pneumatic tire 100 shown in FIG. 9. Two of the sidedecoration bands 166 are formed so as to be disposed at symmetricalpositions sandwiching the tire central axis. Similarly to the firstexemplary embodiment, the marked portions 130 are formed in circular arcshapes at the side portion (see FIG. 9).

As shown in FIG. 14A to FIG. 14C and FIG. 15, in the present exemplaryembodiment, equilateral triangular shapes 162 that are protrusions tothe radial direction outer side (hereinafter referred to as outwardtriangular shapes 162) and equilateral triangular shapes 164 that areprotrusions to the radial direction inner side (hereinafter referred toas inward triangular shapes 164) are formed by the first decorationelements and second decoration elements.

The first decoration elements 170 are formed only by first ridges 176that form outlines of smooth surface regions 174 in the shape ofisosceles triangles with an internal angle of 120°. The seconddecoration elements 172A are constituted by first ridges 176 that formoutlines, and second ridges 178 that are arrayed inside the first ridges176 and have smaller heights than the first ridges 176. In the presentexemplary embodiment, the second ridges 178 extend in the tire radialdirection R.

Each outward triangular shape 162 (see FIG. 14B) is constituted by twoof the first decoration elements 170 that are adjacent to one another,and one of the second decoration elements 172A. In each outwardtriangular shape 162, the second decoration element 172A is formed in aregion of the outward triangular shape 162 excluding the firstdecoration elements 170. Therefore, the shape of the second decorationelement 172A is an isosceles triangle with the same dimensions as eachfirst decoration element 170. The two first decoration elements 170share a first ridge 176P at the region at which they adjoin one another,and the first ridge 176P structures both of these first decorationelements 170.

Each inward triangular shape 164 (see FIG. 14C) is constituted by one ofthe first decoration elements 170 and one of the second decorationelements 172B. In each inward triangular shape 164, the seconddecoration element 172B is formed in a region of the inward triangularshape 164 excluding the first decoration element 170. The second ridges178 with smaller heights than the first ridges 176 are arrayed in thesecond decoration element 172B. In the present exemplary embodiment, adividing ridge 186 that divides the region in which the second ridges178 is formed in two is formed in the second decoration element 172B,extending in a straight line from the center of the inward triangularshape 164 (that is, a vertex of the isosceles triangle formed by thefirst decoration element 170). Cross-sectional dimensions of thedividing ridge 186 are the same as the first ridges 176. Therefore, inappearance, the second decoration element 172B looks like two of thesecond decoration elements 172A that constitute the outward triangularshape 162 adjacent to one another.

The outward triangular shapes 162 and inward triangular shapes 164 arearrayed in a staggered arrangement in the tire radial direction R andthe tire circumferential direction U. That is, the outward triangularshapes 162 and inward triangular shapes 164 are alternately arranged inthe tire circumferential direction U and are alternately arranged in thetire radial direction R. The concept of arranging the outward triangularshapes 162 and inward triangular shapes 164 alternately thus isdescribed in FIG. 15. As shown in FIG. 15, in the present exemplaryembodiment, positions of arrangement of the outward triangular shapes162 and the inward triangular shapes 164 are offset.

According to this constitution, the first decoration elements 170 andthe second decoration elements 172A and 172B are periodically arrangedin each side band 116. The same effects as in the second exemplaryembodiment may be realized with the present exemplary embodiment.

Fifth Exemplary Embodiment

Next, a fifth exemplary embodiment is described. In the presentexemplary embodiment, as shown in FIG. 16, a side decoration band 205 ina circular arc shape is formed at the side portion 114 of the pneumatictire 100 shown in FIG. 9. The side decoration band 205 is formed by acombination of plural first decoration elements 200 and seconddecoration elements 202. Two of the side decoration band 205 are formedso as to be disposed at symmetrical positions sandwiching the tirecentral axis. Similarly to the second exemplary embodiment and the thirdexemplary embodiment, the marked portions 130 are formed at the sideportion (see FIG. 9).

The first decoration elements 200 are formed only by first ridges 206that form outlines of smooth surface regions 204. In the presentexemplary embodiment, the first ridges 206 are constituted by plurallinear ridges whose directions are arbitrary.

The second decoration elements 202 are constituted by the first ridges206 that form that outlines, and second ridges 208 that are arrayedinside the first ridges 126 and have smaller heights than the firstridges 206. The second ridges 208 all extend in the tire radialdirection R.

The concept of forming the first decoration elements 200 and seconddecoration elements 202 thus is described in FIG. 17. As shown in FIG.17, in the present exemplary embodiment, positions of arrangement of thefirst ridges 206 constituting the first decoration elements 200 and thesecond ridges 208 constituting the second decoration elements 202 arenot particularly offset conceptually, but by the first ridges 206 beingdisposed so as to form the first decoration elements 200, sidedecoration band units 205U that constitute the side decoration band 205are formed. Thus, the side decoration band 205 is formed by the sidedecoration band units 205U being continuously arranged in the tirecircumferential direction U.

According to the present exemplary embodiment, even with a simplestructure in which the positions of arrangement of the first decorationelements 200 and the second decoration elements 202 are not periodicallyaligned, because the first ridges 206 have greater heights than thesecond ridges 208, similarly to the second exemplary embodiment, theappearance is significantly improved over a case in which the heightsare the same.

Because the positions of arrangement of the first decoration elements200 and the second decoration elements 202 in one of the side decorationband units 205U are not periodic, the side decoration band 205 in whichthe side decoration band units 205U are arranged continuously in thetire circumferential direction U, that is, the side decoration bandunits 205U are arranged periodically in the tire circumferentialdirection U, appears as if the first decoration elements 200 and thesecond decoration elements 202 with arbitrary shapes are arrangednon-periodically. Therefore, compared to a case in which decorationelements are arranged arbitrarily over the whole of a side decorationband instead of the side decoration band units 205U being formed, theside decoration band 205 that appears to be non-periodic may befabricated much more easily.

Sixth Exemplary Embodiment

Next, a sixth exemplary embodiment is described. In the presentexemplary embodiment, as shown in FIG. 18A and FIG. 18B, a sidedecoration band 216 in a circular arc shape is formed at the sideportion 114 of the pneumatic tire 100 shown in FIG. 9. The sidedecoration band 216 is formed by a combination of plural firstdecoration elements 220 and second decoration elements 222. Two of theside decoration band 216 are formed so as to be disposed at symmetricalpositions sandwiching the tire central axis. Similarly to the secondexemplary embodiment and the third exemplary embodiment, the markedportions 130 are formed at the side portion (see FIG. 9). Peripheryridges 224 are formed at peripheral edge portions at the tire radialdirection outer side and inner side of each side decoration band 216.

Each first decoration element 220 is constituted by first ridges 246that divide up the region and second ridges 248 that are arrayed insidethe first ridges 246.

Each first ridge 246 has a somewhat long, narrow shape and isconstituted by an outer ridge 250 and an inner ridge 252, which isformed to be separated from the outer ridge 250 to the inner side by aconstant spacing. The outer ridge 250 is constituted by outer sideconvex portions 250T, which are formed at each of two length directionends of the outer ridge 250 and each have the shape of a curvedprotrusion to the outer side, and outer side concave portions 250D,which are formed at each of two short direction ends of the outer ridge250 and each have the shape of a curved protrusion to the inner side,that is, the shape of a recess curved from the outer side. The innerridge 252 is constituted by inner side convex portions 252T, which areformed at each of two length direction ends of the inner ridge 252 andeach have the shape of a curved protrusion to the outer side, and innerside concave portions 252D, which are formed at each of two shortdirection ends of the inner ridge 252 and each have the shape of acurved recess from the outer side. The second ridges 248 are ridges thatextend linearly in the length direction of the first decoration elements220.

Each second decoration element 222 is formed in the same shape as thefirst ridges 246 of the first decoration element 220 and is disposedsuch that its orientation is 90° different from the first decorationelement 220. The second ridges 248 are not formed in the seconddecoration element 222. Descriptions hereinafter are given with thestructural elements of the second decoration elements 222 (the firstridges 246 and the second ridges 248) being assigned the same referencenumerals as the structural elements of the first decoration elements220.

The first decoration elements 220 and the second decoration elements 222are arranged periodically in the side decoration band 216. Giving adetailed description, in the side decoration band 216, the firstdecoration elements 220 and the second decoration elements 222 arearranged alternately in the tire circumferential direction U and in thetire radial direction R (in a checkered pattern). The dimensions of theouter side convex portions 250T and the outer side concave portions 250Dare specified in advance (for example, if the outer side convex portions250T and outer side concave portions 250D are formed in circular arcshapes, the radiuses of curvature and arc lengths of the outer sideconvex portions 250T and outer side concave portions 250D are specifiedin advance) such that the outer ridges 250 of the first decorationelements 220 and the outer ridges 250 of the second decoration elements222 connect up without forming angular portions.

As described above, in the present exemplary embodiment, each sidedecoration band 216 in which the first decoration elements 220 andsecond decoration elements 222 are arranged to alternate in the tirecircumferential direction and the tire radial direction R is formed atthe side portion 114. The first decoration elements 220 are constitutedby the first ridges 246 that divide up the region and the linear secondridges 248 that are arrayed inside the first ridges 246. The seconddecoration elements 222 have the same shape as the first ridges 246 ofthe first decoration elements 220 and differ in orientation by 90°.

The first ridges 246 serve the function of framing the decorationpattern, and the second ridges 248 serve the function of improvingvisibility. In each side decoration band 216, because the firstdecoration elements 220 and the second decoration elements 222 arealternately continuous and arranged periodically, uniformity andregularity of the side decoration band 216 are apparent, and unevennessof a region in which the side decoration band 216 is formed may be madeless obvious. Further, because the first ridges 246 have curved shapes,this effect is even more striking. Because the outer ridges 250 of thefirst decoration elements 220 and the outer ridges 250 of the seconddecoration elements 222 are continuous such that angular portions arenot formed, the effect of uniformity and regularity being apparent isfurther provided.

Because the orientations of the first decoration elements 220 and thesecond decoration elements 222 differ by 90°, central directions ofextension of the first ridges 246 differ by 90° and directions ofextension of the second ridges 248 differ by 90°. Thus, the appearance(aesthetics) of the tire side face is further improved.

The respective first ridges 246 of the first decoration elements 220 andthe second decoration elements 222 have curved shapes. Therefore, lightthat is incident from one direction may be reflected over a wide angularrange, and unevenness of the region of the tire may be made even lessobvious.

As shown in FIG. 19, if, in contrast to the present exemplaryembodiment, the first decoration elements and second decoration elementsare formed as a side decoration band 266 that is twisted by 45° to theright in the drawing, the same effects may be realized. As shown in FIG.19, outer ridges 268 may be formed that are disposed only where eachouter ridge opposes a first decoration element and a second decorationelement at both sides, and that appear to be extending in wave shapesalong one direction.

Seventh Exemplary Embodiment

Next, a seventh exemplary embodiment is described. In the presentexemplary embodiment, as shown in FIG. 20, a side decoration band 276 isformed at the side portion 114 of the pneumatic tire 100 shown in FIG.9. In the side decoration band 276, in contrast to the fourth exemplaryembodiment, band-shaped smooth surfaces 280 are formed that are inclined30° to the right in the drawing with respect to the tire radialdirection.

With the present exemplary embodiment, in addition to the effectsrealized in the fourth exemplary embodiment, an effect of improvingappearance with the band-shaped smooth surfaces 280 is realized.

Eighth Exemplary Embodiment

Next, an eighth exemplary embodiment is described. FIG. 21 is a sideview of a pneumatic tire 300 in accordance with the present exemplaryembodiment. As shown in FIG. 21 and FIG. 22A, a side decoration band 316in a circular arc shape (see FIG. 21 and FIG. 22A) is formed at a sideportion 314 of the pneumatic tire 300. The side decoration band 316 isformed by a combination of plural first decoration elements A1, seconddecoration elements B1 and third decoration elements C1. Two of the sidedecoration band 316 are formed so as to be disposed at symmetricalpositions sandwiching a tire central axis CE (see FIG. 21).

At the side portion 314, marked portions 330 are formed in circular arcshapes so as to be adjacent at respective both end portions thereof withone side decoration band 316 and the other side decoration band 316.Thus, two of the marked portions 330 are formed so as to be disposed atsymmetrical positions sandwiching the tire central axis CE. Marks 332are displayed as, for example, the characters “ABCDEFGH”, which arepresented as smooth surfaces. Numerous ridges 334 are arrayed insurrounding regions 336 of the marked portions 330 excluding the marks332.

As shown in FIG. 22A, in each side decoration band 316, plural numbersof the first decoration elements A1, the second decoration elements B1and the third decoration elements C1 are combined periodically. The twoof the side decoration bands 316 are formed so as to be disposed at thesymmetrical positions sandwiching the tire central axis.

Each first decoration element A1 is formed only by first ridges 346 thatform an outline of a smooth surface region 344 in a diamond shape whoselength direction is in the tire circumferential direction U. Ofreflected light from the smooth surface regions 344, reflected lightthat is reflected in the normal direction of the smooth surface regions344 is brightest and is easy to discern.

Each second declaration element B1 is constituted by the first ridges346 forming an outline of a region with a parallelogram shape, which isangled upward to the left in the drawing, and second ridges 349, whichare arrayed inside the first ridges 346 so as to extend in a directionto the upper left of the drawing. Of light reflected from surfaces ofthe second ridges 349, reflected light that is reflected in the normaldirections of these surfaces is brightest and is easy to discern.

Each third declaration element C1 is constituted by the first ridges 346forming an outline of a region with a parallelogram shape, which isangled upward to the right in the drawing, and the second ridges 349,which are arrayed inside the first ridges 346 so as to extend in adirection to the upper right of the drawing. In the present exemplaryembodiment, the directions of extension of the second ridges 349 differby 90° between the second decoration elements B1 and the thirddecoration elements C1.

The first decoration elements A1, second decoration elements B1 andthird decoration elements C1 are structured to share overlapping regionswith one another. In the present exemplary embodiment, the heights ofthe second ridges 349 are lower than those of the first ridges 346.

The first decoration elements A1 are arrayed in lines in the tirecircumferential direction U. The second decoration elements B1 and thirddecoration elements C1 are arrayed alternately in the tirecircumferential direction U. First decoration element rows 354 in whichthe first decoration elements A1 are arrayed in the tire circumferentialdirection U and second decoration element rows 356 in which the seconddecoration elements B1 and third decoration elements C1 are arrayed inthe tire circumferential direction U are alternately arrayed in the tireradial direction R. The first decoration element rows 354 sandwichingeach of the second decoration element rows 356 from both tire radialdirection sides thereof are disposed so as to be offset relative to oneanother in the tire circumferential direction U by half of the tirecircumferential direction length of each decoration element A1. Thesecond decoration element rows 356 sandwiching each of the firstdecoration element rows 354 from both tire radial direction sidesthereof are disposed so as to be offset relative to one another in thetire circumferential direction U by the tire circumferential directionlength of each of the second decoration elements B1 and third decorationelements C1.

The concept of arranging the first decoration elements A1, seconddecoration elements B1 and third decoration elements C1 thus isdescribed in FIG. 23. As shown in FIG. 23, in the present exemplaryembodiment, the first decoration elements A1, second decoration elementsB1 and third decoration elements C1 are formed in matching diamondshapes of which sets of three respectively constitute regular hexagonshapes. Therefore, the first decoration elements A1, second decorationelements B1 and third decoration elements C1 have diamond shapes whoselarge angles are 120° and small angles are 60°.

Positions of arrangement of the first ridges 346, the second ridges 349and the smooth surface regions 344 are specified in advance and thefirst ridges 346, second ridges 349 and smooth surface regions 344 arecombined such that the smooth surface regions 344 are formed inside thefirst ridges 346 at the first decoration elements A1, the inside secondridges 349 are arrayed in the second decoration elements B1, and thesecond ridges 349 are also arrayed in the third decoration elements C1(but the second ridges 349 of the third decoration elements C1 and thesecond ridges 349 of the second decoration elements B1 are arrayed suchthat the extension directions thereof differ by 90°).

According to this structure, the first decoration elements A1, seconddecoration elements B1 and third decoration elements C1 are arrangedperiodically in the side decoration bands 316.

As described above, the side decoration bands 316 are formed at the sideportion 314 in the present exemplary embodiment. In each side decorationband 316, the first decoration elements A1, second decoration elementsB1 and third decoration elements C1 are arranged periodically in thetire circumferential direction U and in the tire radial direction R. Thesmooth surface regions 344 are formed inside the first ridges 346 of thefirst decoration elements A1, the second ridges 349 are arrayed insidethe first ridges 346 of the second decoration elements B1, and thesecond ridges 349 that form angles of 90° with the second ridges 349 ofthe second decoration elements B1 are arrayed in the third decorationelements C1. Therefore, three mutually different kinds of shading(gradations) can be seen in the side decoration band 316. Thus,differences in brightness (light and shade of shadows) due todifferences in reflection directions of light may be effectivelyexhibited by the first decoration elements A1, second decorationelements B1 and third decoration elements C1. At the smooth surfaceregions 344, the reflectance is higher and reflection directions are inthe same direction. Thus, the pneumatic tire 300 may be formed withwhich glossy shades are distinct, a sense of high quality may beimparted, and the appearance (aesthetics) is improved. This isparticularly striking if a wax is applied to the side decoration bands316.

The first ridges 346 have greater heights than the second ridges 349.Therefore, the first ridges 346 serve the function of framing thedecoration pattern and the second ridges 349 serve the function ofimproving the appearance. Thus, the appearance is further improved. Thedimensions of the ridges may be made different by making the machiningdepths different when the ridges are being formed by tooling, etching orthe like.

In each side decoration band 316, the first decoration elements A1,second decoration elements B1 and third decoration elements C1 arecontinuously formed to be periodic. Thus, unevenness of the region inwhich the side decoration band 316 is formed may be made less obvious.

The first ridges 346 forming the outer edges of the first decorationelements A1, second decoration elements B1 and third decoration elementsC1 have the same shapes as one another and have the same ridge heightsas one another. Thus, uniformity and regularity of the side decorationband 316 are strikingly apparent, and a further effect of makingunevenness of the side decoration band 316 less obvious is provided. Ina situation in which incidence angles of light are changing in shortperiods (particularly a situation in which the tire is turning),reflected lights from the first decoration elements A1, seconddecoration elements B1 and third decoration elements C1 can becontinually seen at intervals of certain durations, and the sidedecoration portions appear with strong uniformity and regularity.

The directions of extension of the second ridges 349 differ by 90°between the second decoration elements B1 and the third decorationelements C1. Therefore, the light and shade of shadows changes regularlywhen the pneumatic tire 300 is turning at a turning speed such that thefirst decoration elements A1, second decoration elements B1 and thirddecoration elements C1 can be seen, and the appearance (aesthetics) ofthe side portion 314 is further improved.

In the present exemplary embodiment, the pneumatic tire 100 is providedwith the marked portions 130 at the side portion 114, the markedportions 130 display the marks 132, and the marked portions 130 arerespectively adjacent at both ends to the first decoration elements A1and second decoration elements B1. Thus, the visibility of the markedportions 130 is improved, which is to say, visibility of the marks 132is improved.

The marks 132 are presented as smooth surfaces, and the ridges 34 (forexample, straight or curved ridges) are arrayed in the surroundingregions 136 of the marked portions 130 excluding the marks 132. Thus,the visibility of the marks 132 is further improved and the impact on aperson viewing the marks 132 is substantial. Because two of the sidedecoration bands 316 are formed and the side decoration bands 316 aredisposed at both tire circumferential direction sides of each of themarked portions 130, the marks 132, for which high visibility isimportant, may be made more obvious.

Below, a specific favorable example of the first ridges 346 and secondridges 316, and spacings thereof and suchlike, is illustrated.

FIG. 24 is a sectional diagram viewed from line 4-4 of FIG. 22B. Asillustrated in FIG. 24, each first ridge 346 structuring the seconddecoration elements B1 has a trapezoid shape in cross-section. A widthB12 of a flat surface 346F forming a top portion of the first ridge 346is a maximum of 0.2 mm. Inclined faces (side faces) 346S of the firstridge 346 form angles α10 of 45° with respect to a normal direction N ofthe side decoration band 316. A height h12 of the first ridge 346 is 0.2mm (it is preferable that h12 be in the range from 0.15 to 0.35 mm). Theheight of dividing ridges 338 (see FIG. 21) that extend in the tireradial direction R and divide the side decoration bands 316 from themarked portions 330 is 0.4 mm.

Each second ridge 349 is also a trapezoid in cross-section. A width B22of a flat surface 349F forming a top portion of the second ridge 349 isa maximum of 0.2 mm. Inclined faces (side faces) 349S of the secondridge 349 form angles α20 of 35° with respect to a normal direction N ofthe side decoration band 316. A height h22 of the second ridge 349 is0.15 mm (it is preferable that h22 be in the range from 0.1 to 0.3 mm).A spacing d22 between adjacent second ridges 349 is 0.6 mm.

FIG. 25 is a sectional diagram viewed from line 5-5 of FIG. 22B. Asillustrated in FIG. 25, the cross-sectional dimensions of the firstridges 346 and second ridges 349 structuring the third decorationelements C1 are respectively the same as those of the first ridges 346and second ridges 349 structuring the second decoration elements B1. Aspacing d32 between adjacent ones of these second ridges 349 is 0.8 mm.

Thus, because the inclination angles of the side faces 346S of the firstridges 346 and the side faces 348S of the second ridges 348 aredifferent (α10 and α20 are different), the function of the first ridges346 framing the decoration pattern and the function of the second ridges349 improving the visibility of the pattern may be even more distinctlyserved. Moreover, because of the relationships, h12>h22 and α10>α20,this is realized even further.

A pitch of the second ridges 349 arrayed in the third decorationelements C1 (the spacing d32 between adjacent second ridges 349), islarger than a pitch of the second ridges 349 arrayed in the seconddecoration elements B1 (the spacing d22 between adjacent second ridges349). Thus, the second ridges 349 are arrayed with a higher density inthe second decoration elements B1 than in the third decoration elementsC1. Therefore, a difference in shade may be effectively exhibited by thedifference in pitches between the second decoration elements B1 and thethird decoration elements C1. This is particularly effective for makingbrightness differences between the second decoration elements B1 and thethird decoration elements C1 sufficiently visible when incident amountsof light on the tire side portion are small.

Sufficient effects of visibility, endurance and the like may berealized, provided these dimensions are within a range of ±50% of thevalues illustrated here, preferably within a range of ±30%.

Ninth Exemplary Embodiment

Next, a ninth exemplary embodiment is described. As shown in FIG. 26, ata side portion of a pneumatic tire according to the present exemplaryembodiment, a side decoration band 366 is formed in which, in contrastwith the eighth exemplary embodiment, third decoration elements C2 arearranged instead of the third decoration elements C1 (see FIG. 22B).

In the third decoration elements C2, in contrast with the thirddecoration elements C1 described in the eighth exemplary embodiment, thedirection of extension of the second ridges 349 is the same as that ofthe second ridges 349 of the second decoration elements B1.

In the present exemplary embodiment too, three kinds of mutuallydifferent shading (gradation) can be seen in the side decoration band366, and the same effects as in the eighth exemplary embodiment may beprovided.

Exemplary embodiments of the present invention have been illustrated anddescribed hereabove, but the above exemplary embodiments are merelyexamples and numerous modifications may be embodied within a scope notdeparting from the spirit of the present invention. It will be obviousthat the scope of the present invention is not to be limited to theabove exemplary embodiments.

1. A tire comprising a decoration portion at a tire side portion, thedecoration portion including a plurality of decoration elements, and thedecoration elements including: first decoration elements that are formedonly by first ridges forming decoration element outlines; seconddecoration elements that are configured by the first ridges and secondridges that are arranged inside the first ridges; and third decorationelements that differ from the second decoration elements in terms ofarrangement of the second ridges.
 2. The tire according to claim 1wherein, in the first decoration elements, regions inside the firstridges are smooth surfaces.
 3. The tire according to claim 1, whereindirections of extension of the second ridges differ between the seconddecoration elements and the third decoration elements.
 4. The tireaccording to claim 1, wherein pitches of the second ridges differbetween the second decoration elements and the third decorationelements.
 5. The tire according to claim 1, wherein the first decorationelements, the second decoration elements and the third decorationelements are arranged cyclically in the decoration portion.
 6. The tireaccording to claim 1, further comprising a marked portion at the tireside portion that displays marks, wherein the first decoration elementsand second decoration elements are disposed in at least a portion of aperiphery of the marked portion.
 7. The tire according to claim 6,wherein the ridges are arrayed in a peripheral region of the markedportion that does not include the marks, and the marks are presented assmooth surfaces.